Bug#939904: Temporary network disruption during upgrade

[Raphaël Halimi]

Dear developers,

I just upgraded a sid system and I noticed that the network was broken 
on this machine.

I suppose the reason is that I had systemd-resolved enabled and 
/etc/resolv.conf was symlinked to the stub resolver 
(/run/systemd/resolve/stub-resolv.conf), and since the systemd-resolved 
service had disappeared and didn't respond anymore on 127.0.0.53, the 
system was left with a broken DNS resolution.

On a side note, the changelog says that an entry was added in 
NEWS.Debian to warn user of the change, but it wasn't displayed during 
the upgrade (this is weird, I know). I had to read the changelog to 
understand what was going on.

And finally, my opinion:

After reading the mail thread in this bug report, I thought the plan was 
to separate systemd-resolvconf (as Arch did, IIUC), not the entire 
systemd-resolved service.

IMHO this is a **very** bad idea, and not only because of the broken DNS 
resolution broken after the upgrade in some cases... The whole point of 
systemd-resolved is that it's included in systemd (so basically in every 
Linux system nowadays) and, alongside systemd-networkd, provides an 
entire network configuration/management stack, without the need to 
install optional packages, but most importantly, standard across all 
distributions (no need to learn and/or master ifupdown, sysconfig, 
netplan, whatever, etc).

If it's not too late, I strongly suggest to reintegrate systemd-resolved 
in the main systemd package (as it was before), and split only 
systemd-resolvconf.

Best regards,

-- 
Raphaël Halimi